The municipal government is insisting current car prohibitions in the capital have been a success and led to less congestion and pollution, suggesting decision-makers will continue with the "no-car day" campaign this year.

Beijing Transportation Research Center, a government-funded research organization formed by transportation professors nationwide, said in its annual report that Beijing's overall congestion last year was down 7.4 percent, or 65 minutes shorter, from 2008.

The annual report on the transport situation in the capital also said the car ban ensured vehicle speeds improved by 13.3 per cent and 19.3 per cent respectively during the morning and evening rush hours, compared to 2008.

The report was distributed among speakers during the annual legislative meeting that concluded last week.

Each weekday, around one-fifth of car owners in the capital are banned from driving, based on the last digit of their car license plates. The so-called "no-car day" regulation began at the time of the Beijing Olympics and is set to be reconsidered in April.

Opponents of the ban say authorities do not have the right to stop private car owners from exercising their right to drive for long periods without proper legislation.

They also argue the ban seems to have had little impact because 2,000 new cars are hitting the streets each day and more unskilled drivers are now on the roads, which compromises the effort of the car plate ban.

The city's car population exceeded 4.09 million last week.

Drivers complained that roads were much busier in the days leading up to the travel frenzy around the Lunar New Year.

The report suggested Beijing authorities take more action to limit car use before the city hits six million cars - expected in the next two or three years.

"I'm not saying the current ban is useless, but it's clear the roads have become more crowded," said Fu Liqiang, 48, a cabbie who has been in the business for 13 years. "The government should come up with more solutions and attract more drivers to get off the roads."

Some lawmakers at last week's legislative session urged the local legislative body to draw up a legally binding no-car ban, instead of the disputable government regulation in place at the moment, which has a questionable legal basis.